Bytes In, Bytes Out
This is a simple bytes in, bytes out contract that shows a minimal entrypoint function (denoted by the #[entrypoint] proc macro). If your smart contract just has one primary function, like computing a cryptographic hash, this can be a great model because it strips out the SDK and acts like a pure function or Unix-style app.
src/main.rs
1 #![cfg_attr(not(feature = "export-abi" ), no_main)]
2
3 extern crate alloc ;
4 use alloc :: vec :: Vec ;
5
6 use stylus_sdk :: stylus_proc :: entrypoint ;
7
8 #[entrypoint]
9 fn user_main ( input : Vec < u8 > ) -> Result < Vec < u8 > , Vec < u8 >> {
10 Ok ( input )
11 } 1 #![cfg_attr(not(feature = "export-abi" ), no_main)]
2
3 extern crate alloc ;
4 use alloc :: vec :: Vec ;
5
6 use stylus_sdk :: stylus_proc :: entrypoint ;
7
8 #[entrypoint]
9 fn user_main ( input : Vec < u8 > ) -> Result < Vec < u8 > , Vec < u8 >> {
10 Ok ( input )
11 } Cargo.toml
1 [ package ]
2 name = "bytes_in_bytes_out"
3 version = "0.1.7"
4 edition = "2021"
5
6 [ dependencies ]
7 stylus-sdk = "0.6.0"
8
9 [ features ]
10 export-abi = [ "stylus-sdk/export-abi" ]
11
12 [ profile.release ]
13 codegen-units = 1
14 strip = true
15 lto = true
16 panic = "abort"
17 opt-level = "s"
18
19 [ workspace ] 1 [ package ]
2 name = "bytes_in_bytes_out"
3 version = "0.1.7"
4 edition = "2021"
5
6 [ dependencies ]
7 stylus-sdk = "0.6.0"
8
9 [ features ]
10 export-abi = [ "stylus-sdk/export-abi" ]
11
12 [ profile.release ]
13 codegen-units = 1
14 strip = true
15 lto = true
16 panic = "abort"
17 opt-level = "s"
18
19 [ workspace ] 
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